Open AccessFast automated energy changes at synchrotron radiation beamlines equipped with transfocator or focusing mirrors
Author(s) -
Stepanov Sergey,
Kissick David,
Makarov Oleg,
Hilgart Mark,
Becker Michael,
Venugopalan Nagarajan,
Xu Shenglan,
Smith Janet L.,
Fischetti Robert F.
Publication year - 2022
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577522001084
Subject(s) - beamline , monochromator , undulator , optics , synchrotron radiation , high energy x rays , physics , beam (structure) , lens (geology) , photon energy , photon , wavelength
Algorithms and procedures to fully automate retuning of synchrotron radiation beamlines over wide energy ranges are discussed. The discussion is based on the implementation at the National Institute of General Medical Sciences and the National Cancer Institute Structural Biology Facility at the Advanced Photon Source. When a user selects a new beamline energy, software synchronously controls the beamline monochromator and undulator to maintain the X‐ray beam flux after the monochromator, preserves beam attenuation by determining a new set of attenuator foils, changes, as needed, mirror reflecting stripes and the undulator harmonic, preserves beam focal distance of compound refractive lens focusing by changing the In/Out combination of lenses in the transfocator, and, finally, restores beam position at the sample by on‐the‐fly scanning of either the Kirkpatrick–Baez mirror angles or the transfocator up/down and inboard/outboard positions. The sample is protected from radiation damage by automatically moving it out of the beam during the energy change and optimization.